Terahertz Shielding Properties of Carbon Black Based Polymer Nanocomposites

Abstract

The majority of industry using high-speed communication systems is shifting towards higher frequencies, namely the terahertz range, to meet demands of more effective data transfer. Due to the rising number of devices working in terahertz range, effective shielding of electromagnetic interference (EMI) is required, and thus the need for novel shielding materials to reduce the electromagnetic pollution. Here, we show a study on optical and electrical properties of a series of ethylene co-butyl acrylate/carbon black (EBA/CB) composites with various CB loading. We investigate the transmittance, reflectance, shielding efficiency, absorption coefficient, refractive index and complex dielectric permittivity of the fabricated composites. Finally, we report a material that exhibits superior shielding efficiency (SE)—80 dB at 0.9 THz (14.44 vol% CB loading, 1 mm thick)—which is one of the highest SE values among non-metallic composite materials reported in the literature thus far. Importantly, 99% of the incoming radiation is absorbed by the material, significantly increasing its applicability. The absorption coefficient (α) reaches ~100 cm−1 for the samples with highest CB loading. The EBA/CB composites can be used as lightweight and flexible shielding packaging materials for electronics, as passive terahertz absorbers or as radiation shields for stealth applications.

Dielectric Properties of Hybrid Polyethylene Composites Containing Cobalt Nanoparticles and Carbon Nanotubes

“…The values of the complex dielectric permittivity of the composites with a high concentration of MWCNT (above percolation threshold) in microwaves is quite high (for example, for composites with 13.4 wt% MWCNT and 1.1 wt% Co ε′ ≈ ε″ ≈ 20 at 30 GHz, it corresponds to microwave absorption 50% of 1 mm thick plate in the waveguide [ 32 ]) ( Figure 2 ); therefore, these composites are suitable for electromagnetic applications. The electromagnetic properties of these composites in microwaves are comparable with the best properties of the composites published in literature [ 32 , 33 ]. The dielectric spectra of all investigated composites can be explained by Maxwell–Wagner polarization [ 34 ].…”

Graphene Infused Ecological Polymer Composites for Electromagnetic Interference Shielding and Heat Management Applications

“…In polymer composites, high EMI shielding is usually related to electrical conductivity and the dominant reflection component [ 26 , 27 ]. However, in our previous works, we have already shown a selection of polymer composites with absorption as the main EMI SE component in the terahertz range [ 28 , 29 , 30 ]. The main shielding mechanism can change with the nanocarbon loading in the composite.…”

Flexible composites by ionic liquid/silver/graphene in towel‐gourd sponge fibers: Synergistic effect and dual‐band electromagnetic interference shielding in X‐band and terahertz‐band

“…Beyond this content, absorption coefficient increased rapidly, finally achieved 260 cm −1 at 1 THz with 3 wt% IL, 3 wt% Ag, and 3 wt% rGO loading. Such higher THz shielding effectiveness could be interpreted via the truth that multiple conductive fillers introducing in PA matrix increased charge carriers that strengthens the surficial motilities to reflection for THz wave, and heterogeneous conducting framework resulted in the increased absorption for THz wave 33 …”